Air-feeding device for steam-generators.



No. 828,488. PATENTED 8118.14, 1906. G. D. MOSHER.

AIR PEEDIN-G DEVICE FOR STEAM GENERATORS. APPLIGATION FILED JULY 17, 1803,

2 SHEETS-SHEET l.

PATENTED AUG. 14, 1906.

APPLICATION FILED JULY17, 1903. A

2 SHEETS-SHEET 2.

07u O A! o O AIO m N o \o O T O O o O Inrenorf, C IllMoahe,

,0 e e n f .m

Ml@ JEH-ff U NTTED sTATEs PATENT oEEioE.

CHARLES D. MOSHER, OF NEW YORK, N. Y.

Specification of Letters' Patent. Y

Patented Aug. 14, 1906.

Application filed July 17, 1903. Serial No. 168,055. p

To (1J/t whom it may concern:

Be it known that I, CHARLES D. MosHER, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Air-Feeding Devices for Steam-Generators, of which the following is a specification.

My invention relates to water-tube boilers, and it has special reference to the manner of disseminatin the air-supply and controllin the same an by means of which the heate gases may more readilybe distributed along the generating-tubes and means for holding a baielate in position.

It a so has reference to the particular manner of constructing the combustion-chamber and dividing the same and means for With'- drawing the tubes which constitute the diviion-walls between the combustion-chamers.

The invention further provides a means whereby the tubes may be withdrawn through special openings in the shell or casing Where t e construction requires a water-drumon each side of the steam-drum or where twin furnaces are employed, as will now be set forth in detail.`

In the drawings, Figure 1 is a front view of a boiler, artl 1n section, having twin combustion-c am ers. Fig. 2 is a cross vertical section of a boiler with a single combustionchamber; and Fig. 3, perspective view of portion ofthe enerating-tubes with a section of the bai-Heate located below the upper tier of eneratlng-tubes.

n constructing my invention I provide an elevated steam-drum 4 and one or more Warow of ter-drums 5 on each side of the steam-drum on a lower lane, said Water-drums being connected wit the steam-drum by generatingtubes 6 in the ordinary manner.

In the form of construction shown iirFig. 1, where twin combustion-chambers are used, the steam-drum has two rows of vertical generatin -tubes 7, extending down to and connecte with a smaller water-drum 8, these enerating-tubes being se rated so as to al- Iow rire-brick 9 between t em, and which are thus heldin osition by the tubes. The lower ends .of tlli are rotected by a layer of 4 e-brick 10.

T e u per side of the steam-drum 4 has a oles closed by plugs 11, through which holes the vertical generatin -tubes 7 are withdrawn. The generating-tu es 6 are e tubes ad'acent to the fuelwithdrawn through holes in opposite sides of the steam-drum, these holes being closed normally by plugs 12. p

Above the generating-tubes I place a series of steam-superheating tubes 13, and above the superheating-tubes is a plurality of air-inlet tubes 14, held in place at their upper ends by a header and at their lower ends by a header 16. The chamber 17 at the vupper end of the air-inlet tubes connects with an opening 17 through the boiler-casing fore and aft, and the Ilower ends ofthe inlet-tubes communicate with a channel-way 18, which extends around the rear side of the waterdrum 5 and connects Withthe ash-pit 19. The rear wall of the lire-box has ducts 18',

which communicate with the combustionchamber.

`An interior wall or casing 2O is placed over the air-inlet tubes, and above thls casing is the outer wall or casing 21. The interior casing has an outwardly-opening door or damper 22, which on opening the aperture 23 of the interior casing closes up the. channel or conduit 24, which leads to the stack 25, and also the suction-fan 26, located in the base of the stack. The outer casing also has a pair of outwardly-swinging doors 27 28, so arranged in' position that when the several doors are opened the tubes 6 may be removed therefrom after being Withdrawn from the steam-drum.

In the base of the stack is a central vertical division-Wall 29, the suction-fan being located. in the inner chamber 30 thus formed, above the fan being adam er 31, adapted to swing and cover the cham er 30 or the channel 24. A similar fan is laced on each side above the steam-drum, which fans are operated by a pair ofmotors 32, located in the longitudmal opening 17 through the casin In boilers having a sing e combustionchamber I observe the same arrangement of the generating, superheating, and air-inlet tubes; but the fan 33 in this instance is lob the fan from t air-inlet tubes 14. A similar damper 36 is hinged to the central position wall 37 above the fan, so as to close either of the channels 34 35. As the shaft 38 of the fan and motor pass through the channel I prefer to have it protected by a tube 39as shown.

As it is necessary vvto. have a baffle-plate above the 'series -of tubes it is important it should be held in position firmly, since the ICO cated in the outer space 34, and the air is drawn v e chamber 35 above the ldamper when t rown up to action of the forced draft, operating against the large bathe-plate surface, will raise it causing it to be injured. To provide against this, I locate the baflie-plate 40 below the upper tier of tubes, as shown, for instance, in Figs. 2 and 3, this baflle-plate being of suitably-perforated material and may eX tend from end to end of the generating-tubes or only along the central or 'middle portion of the sets of tubes. I may locate this bailleplate directly below the upper tier of airinlet tubes, as shown at40/ in Fig. l, thus obtaining the advantage of holding it in place without making special holding appliances for this purpose.

The system is operated as follows: In case forced draft is required the suctionsfan 26 is set in motion, which causes the air to pass downwardly through the air-inlet tubes 14,' thence through the channel 18, ash-pit 19, and combustion-chamber, thence in between the generating, superheating, and air-inlet tubes, and out to the stack through the channel 24 and fan 26. It is obvious that the damper 31 is in the meantime closed over the channel 24. lf, on the other hand, natural draft is used, the damper 31 is turned to close the chamber 30, and the products of combustion will pass out the stack through the channel 24 without going through the fan.

The door 22 in the interior casing 20 has a double function. While it is used as a means for closing the o ening 23, it also acts as a the position shown by the dotted line 41. When in that position, the products of combustion cannot pass up to the stack, and when the fire-doors of the furnace on the corresponding side are opened the closing of the channel 24 prevents the fan from 'drawing air into the combustionchamber through the fire-doors. In practice means (not shown) are provided for closing the door 22 whenever the furnace is fired.

It will be seen that the central opening 17 through the casing above the steam-drum permits a ready means for removing the vertical generating-tubes 7, while the generating-tubes 6 can readily be removed through the openings in the interior and outer casing.

What I claim as new is- 1. In a steam-generator, a steam and a water drum parallel with each other and connected bv a lurality of generating-tubes, a combustion-c amber and an ashit below said tubes, a lurality of air-inlet tu es in the path of the fieated gases from the combustion-chamber, parallel with and directly above the generating tubes, a channel around the water-drum communicating with said air-inlet tubes and combustion-chamber, and means for forcing air through said airinlet tubes, channel and into the ash-pit.

2. In a steam-generator, a steam and a water drum parallel with each other and connected by a plurality of generating-tubes, a

plurality of air-inlet tubes parallel with and directly above said generating-tubes, in the path of the heated, ases, a combustionchamber and an ash-pit below the generating-tubes, an air-channel around the waterdrum, communicating with the air-inlet tubes and ash-pit, and a stack having a suction-fan therein.

3. In a steam-generator, a steam and a water drum parallel with each other, and connected by a plurality of generating-tubes, a plurality of air-inlet tubes parallel with and directly above said generating-tubes, an ashpit, an air-channel around the water-drum communicating with the air-inlet tubes and ash-pit, a combustion-chamber having its wall provided with air-ducts which communicate with the air-channel and discharge air above the fire-surface, and a stack having therein means f or drawing air into the`fireborg, and discharging the products of combustion.

4. In a steam-generator, a steam and a Water drum connected together by a plurality of generating-tubes, in combination with a combustion-chamber and ash-pit below said generating-tubes, -a plurality of airinlet tubes parallel with and above the generating-tubes, a channel around-the outer drum connecting the air-inlet tubes vwith the 95 y combustion-chamber and ash-pit, a stack having in its base a suction-fan, a channel leading from the air-inlet tubesto the fan for the gases of combustion, a channel from the fan to the air-inlet tubes for the air, and a roo casing between the two last said channels having means of communication at the upper end of said air-inlet tubes.

5. A steam-generator, comprising a steam and a water drum, connected by generatingto 5 tubes, a combustion-chamber below said tubes, having ducts in its front and rear walls, air-inlet tubes above and arallel with the generating-tubes, a channe around the water-drum communicating with the airrio inlet tubes and combustion-chamber through said ducts, a suction-fan in the stack for supplying air to the combustion-chamber' through the air-inlet tubes, channels and ducts, and a partition-wall above' the fan 115 provided with adjustable openings, as set forth.

6. In a steam-generator, a. steam and a water drum connected by generating-tubes,

a combustion-chamber below said tubes, a 12o plurality of superheater-pipesabove and arallel With the generating-tubes, a suctionan, a casing surrounding said fan and extending transversely across the generator, above the su'perheater-pipes, atop casing 125 connected with theJ transverse casing, sloping downwardly to the rear, and an inner transverse casing extending downwardly from the fan to the up er end of the air-inlet tubes, forming channe s for air and gases of 13o steam-drum withl a combustion, respectively, below and above said inner transverse casing.

` 7. A steam-generator, comprising a single arallel water-drum on each side, connected Iby a set of generating` tubes, and a separate combustion-chamber below each set of generating-tubes, a plurality of-steam superheater-tubes above and parallel with each set of generating-tubes, a casing above said superheater, to form a channel for .the air of combustion, an outer casing to form a channel for the gases of combustion, a stack having a central wall communicating with the division wall or casing between the two channels, having a x 5 suction-fan therein, .and a damper in said division-wall in the stack adapted to close either outlet in said stack, as set forth.

In testimony whereof I ax my signature in presence of two Witnesses. f CHARLES D. MOSHER.

VWitnesses:

THOMAS W. MORRISON; WILLIAM MoLLoY. 

